Note 10 - Intangible Assets - Mortgage Servicing Activity (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Balance, beginning of period	$ 1,724	$ 1,604	$ 1,604
Originations	126	144	675
Amortization	(126)	(124)	(555)
Balance, end of period	1,724	1,624	1,724
Fair value of mortgage servicing rights	$ 3,458	$ 3,043	$ 3,196

Amount of amortization of contract to service financial assets under which estimated future revenue from contractually specified servicing fees, late charges, and other ancillary revenues are not expected to adequately compensate the servicer for performing the servicing.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which estimated future revenues from contractually specified servicing fees, late charges, and other ancillary revenue are not expected to adequately compensate the servicer for performing the servicing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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Amortized amount of contract to service financial assets under which estimated future revenues from contractually specified servicing fees, late charges, and other ancillary revenue are not expected to adequately compensate the servicer for performing the servicing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 1
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Fair value of the servicing liability that has been amortized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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